Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Utility functions for parsing Tegra CVB voltage tables
 *
 * Copyright (C) 2012-2019 NVIDIA Corporation.  All rights reserved.
 */
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/pm_opp.h>
 
#include "cvb.h"
 
/* cvb_mv = ((c2 * speedo / s_scale + c1) * speedo / s_scale + c0) */
static inline int get_cvb_voltage(int speedo, int s_scale,
<------><------><------><------>  const struct cvb_coefficients *cvb)
{
<------>int mv;
 
<------>/* apply only speedo scale: output mv = cvb_mv * v_scale */
<------>mv = DIV_ROUND_CLOSEST(cvb->c2 * speedo, s_scale);
<------>mv = DIV_ROUND_CLOSEST((mv + cvb->c1) * speedo, s_scale) + cvb->c0;
<------>return mv;
}
 
static int round_cvb_voltage(int mv, int v_scale,
<------><------><------>     const struct rail_alignment *align)
{
<------>/* combined: apply voltage scale and round to cvb alignment step */
<------>int uv;
<------>int step = (align->step_uv ? : 1000) * v_scale;
<------>int offset = align->offset_uv * v_scale;
 
<------>uv = max(mv * 1000, offset) - offset;
<------>uv = DIV_ROUND_UP(uv, step) * align->step_uv + align->offset_uv;
<------>return uv / 1000;
}
 
enum {
<------>DOWN,
<------>UP
};
 
static int round_voltage(int mv, const struct rail_alignment *align, int up)
{
<------>if (align->step_uv) {
<------><------>int uv;
 
<------><------>uv = max(mv * 1000, align->offset_uv) - align->offset_uv;
<------><------>uv = (uv + (up ? align->step_uv - 1 : 0)) / align->step_uv;
<------><------>return (uv * align->step_uv + align->offset_uv) / 1000;
<------>}
<------>return mv;
}
 
static int build_opp_table(struct device *dev, const struct cvb_table *table,
<------><------><------>   struct rail_alignment *align,
<------><------><------>   int speedo_value, unsigned long max_freq)
{
<------>int i, ret, dfll_mv, min_mv, max_mv;
 
<------>min_mv = round_voltage(table->min_millivolts, align, UP);
<------>max_mv = round_voltage(table->max_millivolts, align, DOWN);
 
<------>for (i = 0; i < MAX_DVFS_FREQS; i++) {
<------><------>const struct cvb_table_freq_entry *entry = &table->entries[i];
 
<------><------>if (!entry->freq || (entry->freq > max_freq))
<------><------><------>break;
 
<------><------>dfll_mv = get_cvb_voltage(speedo_value, table->speedo_scale,
<------><------><------><------><------>  &entry->coefficients);
<------><------>dfll_mv = round_cvb_voltage(dfll_mv, table->voltage_scale,
<------><------><------><------><------>    align);
<------><------>dfll_mv = clamp(dfll_mv, min_mv, max_mv);
 
<------><------>ret = dev_pm_opp_add(dev, entry->freq, dfll_mv * 1000);
<------><------>if (ret)
<------><------><------>return ret;
<------>}
 
<------>return 0;
}
 
/**
 * tegra_cvb_add_opp_table - build OPP table from Tegra CVB tables
 * @dev: the struct device * for which the OPP table is built
 * @tables: array of CVB tables
 * @count: size of the previously mentioned array
 * @process_id: process id of the HW module
 * @speedo_id: speedo id of the HW module
 * @speedo_value: speedo value of the HW module
 * @max_freq: highest safe clock rate
 *
 * On Tegra, a CVB table encodes the relationship between operating voltage
 * and safe maximal frequency for a given module (e.g. GPU or CPU). This
 * function calculates the optimal voltage-frequency operating points
 * for the given arguments and exports them via the OPP library for the
 * given @dev. Returns a pointer to the struct cvb_table that matched
 * or an ERR_PTR on failure.
 */
const struct cvb_table *
tegra_cvb_add_opp_table(struct device *dev, const struct cvb_table *tables,
<------><------><------>size_t count, struct rail_alignment *align,
<------><------><------>int process_id, int speedo_id, int speedo_value,
<------><------><------>unsigned long max_freq)
{
<------>size_t i;
<------>int ret;
 
<------>for (i = 0; i < count; i++) {
<------><------>const struct cvb_table *table = &tables[i];
 
<------><------>if (table->speedo_id != -1 && table->speedo_id != speedo_id)
<------><------><------>continue;
 
<------><------>if (table->process_id != -1 && table->process_id != process_id)
<------><------><------>continue;
 
<------><------>ret = build_opp_table(dev, table, align, speedo_value,
<------><------><------><------>      max_freq);
<------><------>return ret ? ERR_PTR(ret) : table;
<------>}
 
<------>return ERR_PTR(-EINVAL);
}
 
void tegra_cvb_remove_opp_table(struct device *dev,
<------><------><------><------>const struct cvb_table *table,
<------><------><------><------>unsigned long max_freq)
{
<------>unsigned int i;
 
<------>for (i = 0; i < MAX_DVFS_FREQS; i++) {
<------><------>const struct cvb_table_freq_entry *entry = &table->entries[i];
 
<------><------>if (!entry->freq || (entry->freq > max_freq))
<------><------><------>break;
 
<------><------>dev_pm_opp_remove(dev, entry->freq);
<------>}
}